Nick Clegg, the Liberal Democrat Deputy Prime Minister, has admitted that he
and his party broke a promise to voters over student tuition fees.

Standing in for David Cameron at Prime Minister’s Question Time, he conceded that he had “not been able to deliver the policy that we held in opposition” after abandoning a pledge to scrap university fees altogether.

Instead, the Liberal Democrats last week signed up to Coalition plans to allow institutions to charge up to £9,000 a year.

Harriet Harman, Labour’s deputy leader, claimed that Mr Clegg had “hawked” his way around university campuses seeking student votes ahead of the general election, but had since been “led astray” by the Conservatives in the Coalition Government.

Accusing Mr Clegg of "going along with Tory plans to shove the cost of higher education on to students and their families," she joked: “We all know what it's like: you are at freshers' week, you meet up with a dodgy bloke and you do things that you regret.

"Isn't it true he has been led astray by the Tories, isn't that the truth of it?"

The Liberal Democrat leader responded: "This is an extraordinarily difficult issue and I have been entirely open about the fact that we have not been able to deliver the policy that we held in opposition.

"Because of the financial situation, because of the compromises of the Coalition Government, we have had to put forward a different policy.

"We have stuck to our ambition to make sure that going to university is done in a progressive way so that those people who are presently discouraged from going to university – bright people from poor backgrounds, discouraged by the system we inherited from her government – are able to do so."

Mr Clegg added that the Government’s proposals would see higher earners paying “over the odds” for their education.

Under the plans, outlined last week, successful graduates would be forced to repay student loans at higher rates of interest than those on low incomes.

Mr Clegg said: "The proposals we have put forward will mean that those who earn the least will pay much less than they do at the moment, those who earn the most will pay over the odds to provide a subsidy to allow people from poor backgrounds to go to university."

Asked whether he would accept an invitation from the NUS to meet the protesters, the Deputy Prime Minister declined, saying that he met students regularly.

The Liberal Democrats have incurred the wrath of the demonstrators because all of the party’s MPs signed a National Union of Students pledge to abolish tuition fees before the election in May.

Under the terms of the Coalition Agreement, the Lib Dems are permitted to abstain over the issue, and a number are expected to rebel when the proposal comes before the House of Commons.

As the demonstrations turned into riots, Martin Horwood, Liberal Democrat MP for Cheltenham, was called a “liar” by angry protesters after coming out to address the crowd.

He confirmed that he would not support the new £9,000 tuition fee cap, telling the students: “You don’t know that I’ve lied about anything.”

Meanwhile, Mr Cameron, who is midway through a visit to China and South Korea, has disclosed that the decision to increase tuition fees would help keep the costs down for foreign students coming to Britain.

During a trip to a university in Beijing, the Prime Minister was asked if the plans to raise fees for British students would restrict the opportunities for Chinese youngsters who wished to study in the United Kingdom.

Mr Cameron said increasing tuition fees would mean ''two things,” adding: “It will make sure our universities are well funded ... and we won't go on increasing so fast the fees for overseas students.

''In the past we have been pushing up the fees on overseas students and using that as a way of keeping them down for domestic students. “We have done the difficult thing. We have put up contributions for British students.

“Yes, foreign students will still pay a significant amount of money but we should now be able to keep that growth under control.”

Ministers have said that they expect most institutions to charge less than the new cap of £6,000, which can be raised to £9,000 only in "exceptional circumstances".

But a study by the Higher Education Policy Institute found that all universities will end up charging the £9,000 in order to avoid being seen as "low quality" establishments.